Re: [PATCH] btrfs: replace kcalloc() calls to kzalloc_objs()

[Qu Wenruo <quwenruo.btrfs@gmx.com>]

在 2026/2/24 17:16, Miquel Sabaté Solà 写道:
> Johannes Thumshirn @ 2026-02-24 06:32 GMT:
> 
>> On 2/24/26 12:45 AM, Miquel Sabaté Solà wrote:
>>> Commit 2932ba8d9c99 ("slab: Introduce kmalloc_obj() and family")
>>> introduced, among many others, the kzalloc_objs() helper, which has some
>>> benefits over kcalloc().
>> Namely?
> 
> I didn't want to repeat the arguments from the quoted commit
> 2932ba8d9c99 ("slab: Introduce kmalloc_obj() and family"). Namely:

If you assume every btrfs developer is aware of all slab/mm/vfs/whatever 
subsystem development, then I'd say you're wrong.

Thus you should mention the commit (which is not yet in our developmenet 
tree), and at least have a short reason on the benefit.

> 
>> Internal introspection of the allocated type now becomes possible,
>> allowing for future alignment-aware choices to be made by the
>> allocator and future hardening work that can be type sensitive.
> 
> Should I put this in the commit message as well, regardless of the
> commit explaining this being quoted?
> 
> There's also the argument of dropping 'sizeof' to be more ergonomic. To
> me, though, and considering how these helpers have been applied
> tree-wide, I see this change more as aligning us with this recent
> tree-wide move, which also affected btrfs (see commit 69050f8d6d07
> "treewide: Replace kmalloc with kmalloc_obj for non-scalar types").